/*
   * IRQ chip definitions for INTC IRQs.
   *
   * Copyright (C) 2007, 2008 Magnus Damm
   * Copyright (C) 2009, 2010 Paul Mundt
   *
   * This file is subject to the terms and conditions of the GNU General Public
   * License.  See the file "COPYING" in the main directory of this archive
   * for more details.
   */
  #include <linux/cpumask.h>
  #include <linux/io.h>
  #include "internals.h"

  void _intc_enable(struct irq_data *data, unsigned long handle)

  {

  	unsigned int irq = data->irq;

  	struct intc_desc_int *d = get_intc_desc(irq);
  	unsigned long addr;
  	unsigned int cpu;
  
  	for (cpu = 0; cpu < SMP_NR(d, _INTC_ADDR_E(handle)); cpu++) {
  #ifdef CONFIG_SMP

  		if (!cpumask_test_cpu(cpu, data->affinity))

  			continue;
  #endif
  		addr = INTC_REG(d, _INTC_ADDR_E(handle), cpu);
  		intc_enable_fns[_INTC_MODE(handle)](addr, handle, intc_reg_fns\
  						    [_INTC_FN(handle)], irq);
  	}
  
  	intc_balancing_enable(irq);
  }

  static void intc_enable(struct irq_data *data)

  {

  	_intc_enable(data, (unsigned long)irq_data_get_irq_chip_data(data));

  }

  static void intc_disable(struct irq_data *data)

  {

  	unsigned int irq = data->irq;

  	struct intc_desc_int *d = get_intc_desc(irq);

  	unsigned long handle = (unsigned long)irq_data_get_irq_chip_data(data);

  	unsigned long addr;
  	unsigned int cpu;
  
  	intc_balancing_disable(irq);
  
  	for (cpu = 0; cpu < SMP_NR(d, _INTC_ADDR_D(handle)); cpu++) {
  #ifdef CONFIG_SMP

  		if (!cpumask_test_cpu(cpu, data->affinity))

  			continue;
  #endif
  		addr = INTC_REG(d, _INTC_ADDR_D(handle), cpu);
  		intc_disable_fns[_INTC_MODE(handle)](addr, handle,intc_reg_fns\
  						     [_INTC_FN(handle)], irq);
  	}
  }

  static int intc_set_wake(struct irq_data *data, unsigned int on)

  {
  	return 0; /* allow wakeup, but setup hardware in intc_suspend() */
  }
  
  #ifdef CONFIG_SMP
  /*
   * This is held with the irq desc lock held, so we don't require any
   * additional locking here at the intc desc level. The affinity mask is
   * later tested in the enable/disable paths.
   */

  static int intc_set_affinity(struct irq_data *data,
  			     const struct cpumask *cpumask,
  			     bool force)

  {
  	if (!cpumask_intersects(cpumask, cpu_online_mask))
  		return -1;

  	cpumask_copy(data->affinity, cpumask);

  
  	return 0;
  }
  #endif

  static void intc_mask_ack(struct irq_data *data)

  {

  	unsigned int irq = data->irq;

  	struct intc_desc_int *d = get_intc_desc(irq);
  	unsigned long handle = intc_get_ack_handle(irq);
  	unsigned long addr;

  	intc_disable(data);

  
  	/* read register and write zero only to the associated bit */
  	if (handle) {
  		unsigned int value;
  
  		addr = INTC_REG(d, _INTC_ADDR_D(handle), 0);
  		value = intc_set_field_from_handle(0, 1, handle);
  
  		switch (_INTC_FN(handle)) {
  		case REG_FN_MODIFY_BASE + 0:	/* 8bit */
  			__raw_readb(addr);
  			__raw_writeb(0xff ^ value, addr);
  			break;
  		case REG_FN_MODIFY_BASE + 1:	/* 16bit */
  			__raw_readw(addr);
  			__raw_writew(0xffff ^ value, addr);
  			break;
  		case REG_FN_MODIFY_BASE + 3:	/* 32bit */
  			__raw_readl(addr);
  			__raw_writel(0xffffffff ^ value, addr);
  			break;
  		default:
  			BUG();
  			break;
  		}
  	}
  }
  
  static struct intc_handle_int *intc_find_irq(struct intc_handle_int *hp,
  					     unsigned int nr_hp,
  					     unsigned int irq)
  {
  	int i;
  
  	/*
  	 * this doesn't scale well, but...
  	 *
  	 * this function should only be used for cerain uncommon
  	 * operations such as intc_set_priority() and intc_set_type()
  	 * and in those rare cases performance doesn't matter that much.
  	 * keeping the memory footprint low is more important.
  	 *
  	 * one rather simple way to speed this up and still keep the
  	 * memory footprint down is to make sure the array is sorted
  	 * and then perform a bisect to lookup the irq.
  	 */
  	for (i = 0; i < nr_hp; i++) {
  		if ((hp + i)->irq != irq)
  			continue;
  
  		return hp + i;
  	}
  
  	return NULL;
  }
  
  int intc_set_priority(unsigned int irq, unsigned int prio)
  {
  	struct intc_desc_int *d = get_intc_desc(irq);

  	struct irq_data *data = irq_get_irq_data(irq);

  	struct intc_handle_int *ihp;
  
  	if (!intc_get_prio_level(irq) || prio <= 1)
  		return -EINVAL;
  
  	ihp = intc_find_irq(d->prio, d->nr_prio, irq);
  	if (ihp) {
  		if (prio >= (1 << _INTC_WIDTH(ihp->handle)))
  			return -EINVAL;
  
  		intc_set_prio_level(irq, prio);
  
  		/*
  		 * only set secondary masking method directly
  		 * primary masking method is using intc_prio_level[irq]
  		 * priority level will be set during next enable()
  		 */
  		if (_INTC_FN(ihp->handle) != REG_FN_ERR)

  			_intc_enable(data, ihp->handle);

  	}
  	return 0;
  }

  #define SENSE_VALID_FLAG 0x80
  #define VALID(x) (x | SENSE_VALID_FLAG)

  
  static unsigned char intc_irq_sense_table[IRQ_TYPE_SENSE_MASK + 1] = {
  	[IRQ_TYPE_EDGE_FALLING] = VALID(0),
  	[IRQ_TYPE_EDGE_RISING] = VALID(1),
  	[IRQ_TYPE_LEVEL_LOW] = VALID(2),
  	/* SH7706, SH7707 and SH7709 do not support high level triggered */
  #if !defined(CONFIG_CPU_SUBTYPE_SH7706) && \
      !defined(CONFIG_CPU_SUBTYPE_SH7707) && \
      !defined(CONFIG_CPU_SUBTYPE_SH7709)
  	[IRQ_TYPE_LEVEL_HIGH] = VALID(3),
  #endif

  #if defined(CONFIG_ARM) /* all recent SH-Mobile / R-Mobile ARM support this */

  	[IRQ_TYPE_EDGE_BOTH] = VALID(4),
  #endif

  };

  static int intc_set_type(struct irq_data *data, unsigned int type)

  {

  	unsigned int irq = data->irq;

  	struct intc_desc_int *d = get_intc_desc(irq);
  	unsigned char value = intc_irq_sense_table[type & IRQ_TYPE_SENSE_MASK];
  	struct intc_handle_int *ihp;
  	unsigned long addr;
  
  	if (!value)
  		return -EINVAL;

  	value &= ~SENSE_VALID_FLAG;

  	ihp = intc_find_irq(d->sense, d->nr_sense, irq);
  	if (ihp) {

  		/* PINT has 2-bit sense registers, should fail on EDGE_BOTH */
  		if (value >= (1 << _INTC_WIDTH(ihp->handle)))
  			return -EINVAL;

  		addr = INTC_REG(d, _INTC_ADDR_E(ihp->handle), 0);

  		intc_reg_fns[_INTC_FN(ihp->handle)](addr, ihp->handle, value);

  	}
  
  	return 0;
  }
  
  struct irq_chip intc_irq_chip	= {

  	.irq_mask		= intc_disable,
  	.irq_unmask		= intc_enable,
  	.irq_mask_ack		= intc_mask_ack,
  	.irq_enable		= intc_enable,
  	.irq_disable		= intc_disable,
  	.irq_shutdown		= intc_disable,
  	.irq_set_type		= intc_set_type,
  	.irq_set_wake		= intc_set_wake,

  #ifdef CONFIG_SMP

  	.irq_set_affinity	= intc_set_affinity,

  #endif
  };